Artist's depiction of zig-zag lines appearing as part of a migraine aura phenomenon

An aura is the perceptual disturbance experienced by some migraine sufferers before a migraine headache, and the telltale sensation experienced by some people with epilepsy before a seizure. It often manifests as the perception of a strange light, an unpleasant smell or confusing thoughts or experiences.

When occurring, auras allow epileptics time to prevent injury to themselves. The time between the appearance of the aura and the migraine lasts from a few seconds up to an hour. Most people who have auras have the same type of aura every time.

Auras can also be confused with sudden onset of panic, panic attacks or anxiety attacks creating difficulties in diagnosis. The differential diagnosis of patients who experience symptoms of paresthesias, derealization, dizziness, chest pain, tremors, and palpitations can be quite challenging.^[1]

An aura sensation can include some or a combination of the following:

• Visual Changes.
  • Bright lights.
  • Zigzag lines.
  • Distortions in the size or shape of objects.
  • Vibrating visual field.
  • scintillating scotoma
    • Shimmering, pulsating patches, often curved.
    • Tunnel vision
  • scotoma
    • Blind or dark spots in the field of vision.
    • Curtain-like effect over one eye.
    • Slowly spreading spots.
  • Kaleidoscope effects on visual field
  • Total temporary monocular (in one eye) blindness (in retinal migraine)^[2].
• Auditory changes
  • Hearing voices or sounds that do not exist: true auditory hallucinations.
  • Modification of voices or sounds in the environment: buzzing, tremolo, amplitude modulation or other modulations.
• Strange smells (Phantosmia).
• Feelings of numbness or tingling on one side of the face or body.
• Feeling separated from one's body.
• Feeling as if the limbs are moving independently from the body.
• Feeling as if one has to eat or go to the bathroom.
• Anxiety or fear.
• Nausea.
• Weakness, unsteadiness.
• Saliva collecting in the mouth.
• Being unable to understand or comprehend spoken words during and after the aura.
• Being unable to speak properly, despite the brain grasping what the person is trying to verbalize. (Aphasia)

The specific type of sensation associated with an aura can potentially be used in an attempt to localize the focus of a seizure.

Auras share similar symptoms with strokes, but onset is more gradual with auras.^[3] Auras can last from several seconds to several minutes and can sometimes end with feelings of extreme tiredness, weakness, heart palpitation, sweating and warmth throughout one's body.

[edit] See also

• Hallucination
• Paresthesia
• Synesthesia
• Simple partial seizure
• Complex partial seizure

[edit] References

[edit] External links

• About.com aura summary
• Epilepsy.com information
• Migraine Aura Foundation
• MAGNUM, the National Migraine Association
• Epilepsy Action information
• Migraines with 'aura' raise women's stroke risk